diff --git a/arch/i386/kernel/irq.c b/arch/i386/kernel/irq.c
index f3a9c78c4a24412cfea2cddbe8d1c1e51eb00bea..248e922ee13a14b0cf0e97ce5261f92db141bba6 100644
--- a/arch/i386/kernel/irq.c
+++ b/arch/i386/kernel/irq.c
@@ -42,8 +42,8 @@ union irq_ctx {
 	u32                     stack[THREAD_SIZE/sizeof(u32)];
 };
 
-static union irq_ctx *hardirq_ctx[NR_CPUS];
-static union irq_ctx *softirq_ctx[NR_CPUS];
+static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
+static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
 #endif
 
 /*
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index bfcec4cc70a705c58f208e97645c3714887866b6..40d4c14fde8fa2ae3333062786688584b3387757 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -380,8 +380,8 @@ unsigned int real_irq_to_virt_slowpath(unsigned int real_irq)
 #endif /* CONFIG_PPC64 */
 
 #ifdef CONFIG_IRQSTACKS
-struct thread_info *softirq_ctx[NR_CPUS];
-struct thread_info *hardirq_ctx[NR_CPUS];
+struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
+struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
 
 void irq_ctx_init(void)
 {